Exhaust or blower fan



' (No Model.)

w. W. GREEN & L. G. STARK.. Exhaust or Blower Fan.

No. 236,804.. Patent ed Jan. 18, 188i.

' MAY'J" Li A Wan/am A Fl? I i gggmyzfm/d v40 Jiiarnyw 0 UNITED STATES PATENT OFFICE.

WILLIAM W. GREEN AND LEWIS G. STARK, OF CHICAGO, ILLINOIS.

EXHA'UST OR BLOWER FAN.

SPECIFICATION forming part of Letters Patent No. 236,804, dated January 18, 1881.

Application filed August 28, 1880.

To all whom 'it may concern:

Be it known that we, WILLIAM W. GREEN and LEwIs G. STARK, of Chicago, in the county of Cook and State of Illinois, have invented certaiu-new and useful Improvements in Exhaust and Blowing Fans; and we do hereby declare the following to be a full, clear, and exact description of the invention, that will enable others skilled in the art to which it appertains to construct and make use of the same, reference being had to the accompanying drawings, and the letters of reference marked thereon, forming a part of this specification.

The object of this invention is an improvement in exhaust or blower fans adapted to be used for the varied purposes to which mechanism of this nature is usually applied; and it consists of certain novel features and arrangement of the parts, as will be hereinafter more fully described in detail.

Figure 1 is a view in perspective Fig. 2, a vertical longitudinal section in the plane 2 2, Fig. 1 and Fig. 3, a vertical transverse section in the plane 3 3, Fig. 2.

Referring to the drawings, A represents a cylindrical casing or shell inclosing the fanwheels; B, shaft; G, boxes forming bearings for the shaftB; A, pulleys for the reception of driving-belts D D, the series of wings forming the fan-wheels; a at, arms connecting the series of wings to the shaft B, and 0 legs attached to the lower part of the casing.

As herein shown, two fan-wheels are employed, forming, properly, a double fan, which are located at a point near each end of the shaft B, as shown in Fig. 2 of the drawings. As here shown, four wings or blades enter into the formation of each fan. These wings, forming the two fan-wheels, do not lie in aparallel plane, but are placed at alternate points on the shaft B-that is, when one of the wings of one fan-wheel is at the top, and the companion wing is on the quarter of the circle of revolution, the wings on the opposite fan are set at a point equidistant betweenthe two wings on the opposite fan in the plane of revolution. By this arrangement the two fans of four wings each are enabled to cut the air at eight difl'erent points at each revolution, thus in- (No model.)

Furing a continuous and steady motion of the ans.

Another of the essential features of this improvement is the central suction or inlet-passage, a. The air is received at this point and passes to the fans, as indicated by arrows in Fig. 2 of the drawings, a a being dischargeoutlets froim each fan.

The advantages of this form of construction are, that by placing two or more fans on the same shaft, and havinga central suction, enables fans of a much less diameter to exert more power and do better work than it is possible to do with fans of double the diameter of the ordinary form and construction, and it takes less power to drive this fan. The central suction readily permits of a spout or connection leading off in any desired direction.

The casing inclosing the fans is divided through the center in a horizontal plane, for the purpose of conveniently giving access to the fans for examination and repairs.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-

l. A double fan having the wings or blades forming the fan-wheels proper placed on the same shaft and arranged alternately in the plane of revolution relative to each other, combined with an inclosing-case which has a central air-inlet common to both of said fans, substantially as described.

2. In a double fan, the blades whereof are arranged in alternate planes, as hereinbefore 

